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Re: Modified Retard Capsule Re-Visited - Followup Posted by Saabina [Email] (#33) [Profile/Gallery] (more from Saabina) on Wed, 15 Nov 2017 18:39:46 In Reply to: Modified Retard Capsule Re-Visited, Saabina [Profile/Gallery] , Sun, 12 Nov 2017 11:30:33 Members do not see ads below this line. - Help Keep This Site Online - Signup |
For those interested, I restricted the flow by cinching the tube between the throttle body and dizzy capsule with a wrap of SS aircraft safety wire. I believe I cut the flow by about half but did not measure it. The result was a definite positive. Seamless acceleration from NA to boost and a much smoother and quicker throttle response without that annoying flat spot. It's kinda funny since the typical delayed surge was gone making me wonder if I had somehow lost power. Until I looked at the speedometer... And, the boost gauge now seems directly attached to my foot rather than the back seat. Finally, no loss of drive-ability during stop and go or highway and idle remained solid. I'm stoked.
Next task is to make a simple, adjustable in-line flow controller and fine tune it.
Analysis
The dizzy capsule is a pressure actuated, fixed volume, spring-loaded mechanical servo. You can slow the response three ways:
1) Increase the spring rate to delay the response by requiring a higher input pressure.
2) Decrease the input pressure by bleeding to delay the response with the stock spring.
3) Decrease the input flow to delay the response with the stock spring.
Correct me if I am wrong but I believe they are all equivalent.
Disclaimer: '93 c900 with stock Mitsu TE05 turbo, -08 Dizzy, Red Box APC, 2.8 FPR, 24# Blue Densos and timing at 15BTDC.
posted by 108.243.204...
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